A low-carbon purification of multi-phase extraction tail gas biological trickling tower rapid biofilm formation method

Abstract

This invention relates to a rapid biofilm formation method for low-carbon purification of multiphase extraction tail gas using a biotrickling filter, comprising the following steps: (1) placing highly efficient degrading bacteria in a culture medium supplemented with benzene series compounds for expansion culture to obtain a highly efficient degrading bacteria suspension; (2) mixing the highly efficient degrading bacteria suspension with activated sludge to obtain a composite bacterial suspension; (3) adding the composite bacterial suspension and nutrient solution to the biotrickling filter for inoculation, and introducing benzene series compounds, so that the composite bacterial community can undergo gas-liquid phase synchronous acclimatization and biofilm formation in the biotrickling filter, thus completing the process. Compared with the prior art, the biofilm formation enhanced method based on a biotrickling filter provided by this invention can form a biofilm and start up within 21 days, when the inlet concentration of toluene waste gas is 600 mg / m³. 3 At this time, the removal rate of toluene can reach 91.36%. This operation has low operating costs, minimal negative impact on the environment, and has good prospects for development and utilization.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of microbial treatment equipment and relates to a low-carbon biological trickling filter tower rapid biofilm formation method for purifying multi-phase extraction tail gas. BACKGROUND

[0002] In view of the underground water and soil remediation work of a gas station in a petrochemical site, due to the characteristics of the site in service, limited site area and many sensitive points around, in the process of using multi-phase extraction technology to repair the contaminated site, extraction tail gas is generated, in order to prevent the extraction tail gas from affecting the surrounding sensitive points such as residential areas, the tail gas needs to be purified. The multi-phase extraction tail gas has the characteristics of high water content and large fluctuation of pollutant load, and when treating high water content gas, the traditional activated carbon adsorption usually causes low utilization rate of activated carbon because water gas occupies most of the adsorption sites, and the activated carbon adsorbing pollutants needs to be treated as hazardous waste, which has high treatment cost. The biological trickling filter tower is a green, low-carbon and efficient extraction tail gas treatment technology through the growth and metabolism of microorganisms to degrade pollutants, and has attracted much attention in recent years, but the current biofilm formation of the biological trickling filter tower has the problems of long cycle, slow start and large fluctuation of treatment effect of non-steady-state extraction tail gas, which limits the large-scale promotion and use of the biological trickling filter tower, and a method for rapidly starting the biofilm formation of the biological trickling filter tower is urgently needed.

[0003] The biological trickling filter tower needs to be started by biofilm formation in the initial stage of operation and use, and this link determines the length of time required for the biological trickling filter tower to enter the formal operation stage and also determines the removal efficiency of pollutants in the formal operation stage. In the traditional biofilm formation method, activated sludge is used for strain domestication, and then biofilm formation is performed, and the domestication stage is usually slow, thus resulting in a long cycle of starting and putting into formal operation.

[0004] Chinese patent CN 106039983 A discloses a biofilm formation and starting method of a biological trickling filter system for degrading hydrophobic volatile organic compounds, in which the activated sludge is first domesticated outside the tower by liquid hydrophobic volatile organic compounds, then high mass concentration easily biodegradable substrates are used as the only carbon source for rapid biofilm formation, and then the biological trickling filter system is started by a gas-liquid combined method. The method can realize strain biofilm formation within 2-3 days and complete the starting of the biological trickling filter system within 10-15 days, but a sludge domestication period of 30 days is needed before biofilm formation, and the whole domestication and starting cycle is about 45 days. SUMMARY

[0005] The purpose of the present application is to provide a low-carbon biological trickling filter tower rapid biofilm formation method for purifying multi-phase extraction tail gas, in particular a biological trickling filter tower rapid biofilm formation and starting method for treating multi-phase extraction repair tail gas of a petrochemical site, so as to realize the rapid biofilm formation and starting of the biological trickling filter tower.

[0006] The purpose of the present application can be realized by the following technical solutions.

[0007] One of the technical solutions of the present application provides a low-carbon purification of multi-phase extraction tail gas biotrickling tower rapid biofilm formation method, comprising the following steps:

[0008] (1) Take the high-efficiency degrading bacteria and place them in the culture medium added with benzene series to carry out the expansion culture, and obtain the high-efficiency degrading bacteria suspension;

[0009] (2) Mix the high-efficiency degrading bacteria suspension with the activated sludge to obtain the composite bacteria group suspension;

[0010] (3) Then, the composite bacteria group suspension and the nutrient solution are added to the biotrickling tower for inoculation, and the benzene series gas is input, so that the composite bacteria group is subjected to the gas-liquid phase synchronous domestication and biofilm formation in the biotrickling tower, and the process is completed.

[0011] Further, the high-efficiency degrading bacteria are selected from at least one of the following kinds:

[0012] The benzene series degrading bacterial strain Corynebacterium sp. AL-5 has the preservation number CCTCC NO. M2020503, or the Achromobacter sp. ED-2 has the preservation number CCTCC NO. M 2021058, or the Diaphorobacter sp. ED-3 has the preservation number CCTCC NO. M 2021059. These high-efficiency degrading bacteria are all known bacteria species disclosed in the prior art, and can be directly purchased from the preservation center. For details, refer to the previous patent application of the applicant.

[0013] Further, the OD 600 value of the high-efficiency degrading bacteria suspension is 0.8-1.5.

[0014] Further, in step (1), the benzene series in the culture medium added with benzene series is toluene, and the concentration thereof is 20 mg / L.

[0015] Further, in step (2), the volume ratio of the high-efficiency degrading bacteria suspension to the activated sludge is 0.5-1:1.

[0016] Further, in step (2), the activated sludge used is from a water treatment plant, and the SV thereof is 30%-50% and the SVI thereof is 60-100.

[0017] Further, in step (3), the nutrient solution is configured by 0.2 g / L NH4Cl, 7.95 g / L NaCl, 0.77 g / L MgCl2·6H2O, 1.05 g / L MgSO4·7H2O, 0.076 g / L CaCl2, 0.22 g / L KCl, 0.01 g / L NaHCO3, 0.026 g / L NaBr, 0.25 g / L K2HPO4, 0.2-1.0 g / L yeast powder, and trace elements. More specifically, the trace element mother liquor comprises 0.15 g / L ZnSO4·7H2O, 0.26 g / L MnSO4·H2O, 0.03 g / L CoCl2·6H2O, 4.5 g / L FeSO4·7H2O, 0.02 g / L NiCl2·6H2O, 0.01 g / L CuCl2, 0.1 g / L Na2MoO4·2H2O, and 0.06 g / L H3BO3, and 1 mL of the trace element mother liquor is added per liter of the nutrient solution.

[0018] Further, in step (3), the nutrient solution further contains a benzene series component, and the benzene series is toluene, the mass concentration of which is increased by 10 mg / L per day from 0 mg / L on the first day of the biofilm formation, and is gradually increased to 30-60 mg / L and then terminated.

[0019] Further, in step (3), the benzene series gas is toluene dilution gas, the mass concentration of which is increased by 50-100 mg / m 3 per 1-2 days from 50-100 mg / m 3 on the first day of the biofilm formation, and is gradually increased to 400-1000 mg / m 3 .

[0020] Further, in step (3), the carrier loaded in the biological trickling filter tower is polyurethane sponge filler.

[0021] Compared with the prior art, the biofilm formation strengthening method based on the biological trickling filter tower provided by the application can form a biofilm and start up within 21 days, and the removal rate of toluene can reach 91.36% when the inlet concentration of toluene waste gas is 400-1000 mg / m 3 . The operation cost is low, the negative impact on the environment is small, and the method has a good development and utilization prospect. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The scanning electron microscope image of the surface biofilm of the polyurethane sponge filler provided by the application;

[0023] Figure 2 The device flow diagram of the biological trickling filter tower;

[0024] Figure 3A diagram of the inlet concentration, outlet concentration and removal rate of toluene in the process of strengthening the biofilm formation in the bio-trickling tower;

[0025] Figure 4 A diagram of the removal rate of toluene in the bio-trickling tower and activated carbon adsorption under different inlet relative humidity;

[0026] Figure 5 A diagram of the removal rate of toluene in the bio-trickling tower under different spraying amounts;

[0027] Figure 6 A diagram of the removal rate of toluene in the bio-trickling tower under concentration fluctuation conditions. DETAILED DESCRIPTION

[0028] The present application will be described in detail below in conjunction with the accompanying drawings and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present application, and gives a detailed implementation and specific operation process, but the protection scope of the present application is not limited to the following examples.

[0029] In the following embodiments or examples, if no special description is made for the raw materials or processing techniques, it is indicated that they are all conventional commercially available raw materials or conventional processing techniques in the art.

[0030] In order to realize the rapid biofilm formation and start-up of the bio-trickling tower, the present application provides a rapid biofilm formation method of a low-carbon purification multi-phase extraction tail gas bio-trickling tower, comprising the following steps:

[0031] (1) Taking the high-efficiency degrading bacteria and placing them in the culture medium added with benzene series to carry out the expansion culture, and obtaining the high-efficiency degrading bacteria suspension;

[0032] (2) Mixing the high-efficiency degrading bacteria suspension with the activated sludge to obtain the composite bacterial community suspension;

[0033] (3) Adding the composite bacterial community suspension and the nutrient solution into the bio-trickling tower for inoculation, and inputting the benzene series gas, so that the composite bacterial community is subjected to the gas-liquid phase synchronous domestication and biofilm formation in the bio-trickling tower, and the process is completed.

[0034] In some specific embodiments, the high-efficiency degrading bacteria are benzene series degrading bacterial strains Corynebacterium sp. AL-5 with the preservation number CCTCC NO. M2020503, Achromobacter sp. ED-2 with the preservation number CCTCC NO. M2021058, or Diaphorobacter sp. ED-3 with the preservation number CCTCC NO. M2021059. These high-efficiency degrading bacteria are all known bacterial species disclosed in the art, and can be directly purchased from the preservation center, as can be seen from the previous patent applications of the applicant.

[0035] In some embodiments, the OD value of the bacterial suspension of the high-efficiency degrading bacteria is 0.8-1.5. 600

[0036] In some embodiments, in step (1), the benzene series in the culture medium is toluene, and the concentration is 20 mg / L.

[0037] In some embodiments, in step (2), the volume ratio of the bacterial suspension of the high-efficiency degrading bacteria to the activated sludge is 0.5-1:1.

[0038] In some embodiments, in step (2), the activated sludge used is from a water treatment plant, and the SV is 30%-50% and the SVI is 60-100.

[0039] In some embodiments, in step (3), the nutrient solution is configured by 0.2 g / L NH4Cl, 7.95 g / L NaCl, 0.77 g / L MgCl2·6H2O, 1.05 g / L MgSO4·7H2O, 0.076 g / L CaCl2, 0.22 g / L KCl, 0.01 g / L NaHCO3, 0.026 g / L NaBr, 0.25 g / L K2HPO4, 0.2-1.0 g / L yeast powder, and trace elements. More specifically, the composition of the trace element mother liquor is 0.15 g / L ZnSO4·7H2O, 0.26 g / L MnSO4·H2O, 0.03 g / L CoCl2·6H2O, 4.5 g / L FeSO4·7H2O, 0.02 g / L NiCl2·6H2O, 0.01 g / L CuCl2, 0.1 g / L Na2MoO4·2H2O, and 0.06 g / L H3BO3, and 1 mL of the trace element mother liquor is added per liter of the nutrient solution.

[0040] In some embodiments, in step (3), the nutrient solution also contains benzene series components, and the benzene series is toluene, and the mass concentration is increased by 10 mg / L per day from 0 mg / L on the first day of the biofilm formation, and the addition is terminated after gradually increasing to 30-60 mg / L.

[0041] In some embodiments, in step (3), the benzene series gas introduced is toluene dilution gas, and the mass concentration is increased by 50-100 mg / m 3 every 1-2 days from 50-100 mg / m 3 on the first day of the biofilm formation, and gradually increased to 400-1000 mg / m 3 .

[0042] In some embodiments, in step (3), the carrier loaded in the bio-trickling tower is polyurethane sponge filler.​

[0043] The above embodiments can be implemented individually or in any two or more combinations.

[0044] The above embodiments will be described in more detail below in conjunction with specific examples.

[0045] Unless otherwise specified, the culture medium formula used is as follows:

[0046] Formula of LB medium: 10 g / L peptone, 5 g / L yeast powder, 10 g / L NaCl.

[0047] Formula of inorganic nutrient solution: 0.2 g / L NH4Cl, 7.95 g / L NaCl, 0.77 g / L MgCl2·6H2O, 1.05 g / L MgSO4·7H2O, 0.076 g / L CaCl2, 0.22 g / L KCl, 0.01 g / L NaHCO3, 0.026 g / L NaBr, 0.25 g / L K2HPO4, 0.6 g / L yeast powder, and trace elements. The trace elements are introduced by trace element mother liquor, and the composition is as follows: 0.15 g / L ZnSO4·7H2O, 0.26 g / L MnSO4·H2O, 0.03 g / L CoCl2·6H2O, 4.5 g / L FeSO4·7H2O, 0.02 g / L NiCl2·6H2O, 0.01 g / L CuCl2, 0.1 g / L Na2MoO4·2H2O, 0.06 g / L H3BO3, and 1 mL of trace element mother liquor is added per liter of nutrient solution.

[0048] The activated sludge is taken from a water treatment plant, and the SV = 40% and the SVI = 80.

[0049] The bio-trickling tower is as follows: Figure 2As shown, it includes air pump 1, gate valve 2, gas flow meter 3, toluene gas generating bottle 4, humidification gas generating bottle 5, mixing buffer bottle 6, biological trickling filter tower 7, nutrient solution storage tank 8, peristaltic pump 9, gas sampling hole 10, perforated plate 11, rotor flow meter 12, activated carbon adsorption tank 13, filler 14, sprayer 15. When the biological trickling filter tower 7 is running, air is pumped by the air pump, and the inlet air flow is measured and adjusted by the gas flow meter 3 and the gate valve 2 respectively. The inlet air enters the toluene gas generating bottle 4 (the water bath temperature is controlled by the temperature controller to ensure that the toluene vapor pressure is in a stable state) and the humidification gas generating bottle 5, the toluene gas generating bottle 4 is placed in the water bath, and toluene gas and humidification gas of a certain concentration are generated respectively and enter the mixing buffer bottle 6 for mixing, and then enter the biological trickling filter tower 7 from the bottom of the reactor. The nutrient solution is stored in the nutrient solution storage tank 8, pumped to the top of the reactor by the peristaltic pump 9, sprayed to the surface of the filler by the sprayer, and finally returned to the nutrient solution storage tank 8, forming a cycle.

[0050] Example 1

[0051] Corynebacterium sp. AL-5, Achromobacter sp. ED-2, and Diaphorobacter sp. ED-3, which are three strains of benzene series high-efficiency degrading bacteria, were cultured in a culture medium. The three strains were respectively added into 300 mL of LB culture medium and placed in a shaker with a temperature of 30°C and a rotation speed of 180 r / min for culture. After the culture was completed, high-efficiency degrading bacteria suspensions A, B, and C were respectively obtained, and the OD values of the bacterial suspensions were 1.5. Then, the high-efficiency degrading bacteria suspensions A, B, and C were mixed to obtain a mixed bacteria suspension D. 600

[0052] The mixed bacteria suspension D and activated sludge were mixed in a volume ratio of 1:1 to obtain a benzene series high-efficiency degrading bacteria composite bacteria suspension, and the composite bacteria suspension was transferred to a bacteria barrel. The activated sludge was obtained from a sewage treatment plant and needed to be screened and filtered with a 60-mesh screen to remove impurities in the activated sludge. The filtered activated sludge was exposed to air for 48 h, and the purpose was to let the microorganisms consume the organic matter in the activated sludge.

[0053] Polyurethane sponge filler was added to the bacteria barrel containing the composite bacteria suspension, soaked for 24 h, and inoculated once. After the soaking was completed, the filler was transferred to the biological trickling filter tower.

[0054] The composite bacteria suspension was transferred to the nutrient solution tank, and the filler was circularly sprayed with the bacteria suspension for 24 h for secondary inoculation. The spraying amount was 60 mL / min, and the spraying amount should not be too small or too large, so as to prevent the inoculated microorganisms from lacking sufficient nutrients or being washed off.

[0055] ​After spraying the complex bacteria suspension, the bacteria suspension was drained, and gas-liquid phase synchronous acclimation and biofilm formation were performed. The biofilm formation conditions were as follows: temperature 25°C, gas flow rate 4 L / min, spraying amount 60 mL / min, and pH value of nutrient solution 7.0. In the initial stage of biofilm formation, the circulating spraying nutrient solution (the inorganic nutrient solution contains 0.2 g / L NH4Cl, 7.95 g / L NaCl, 0.77 g / L MgCl2·6H2O, 1.05 g / L MgSO4·7H2O, 0.076 g / L CaCl2, 0.22 g / L KCl, 0.01 g / L NaHCO3, 0.026 g / L NaBr, 0.25 g / L K2HPO4, 0.5 g / L yeast powder, and trace elements (10 3 :1) by volume) was used, and air was introduced. 3 Starting from 0 mg / m 3 g / L on the first day of biofilm formation, the concentration of emulsified toluene in the nutrient solution was gradually increased by 10 mg / L per day, and the concentration of toluene in the introduced gas was gradually increased by 50 mg / m 3 g / L every 2 days, to 600 mg / m 3 g / L, so that the microorganisms could gradually adapt to high concentrations of pollutants.

[0056] When the removal rate of toluene with a concentration of 600 mg / m 3 was more than 75% and remained stable for about 2-3 days, the biofilm formation was considered to be completed.

[0057] Example 2

[0058] The biofilm formation was performed by the method of Example 1, the toluene gas flow rate was 4 L / min, and the toluene concentration was 100 mg / m 3 . The toluene concentration of the gas at the inlet and outlet of the bio-trickling tower was detected by gas chromatography.

[0059] The toluene concentration at the inlet and outlet of the waste gas and the removal rate changed with the biofilm formation time as shown in Table 1. When the inlet concentration reached 400 mg / m 3 g / L after 16 days of biofilm formation, the removal rate was more than 90%. After that, the inlet concentration was further increased, but the removal rate did not decrease significantly and remained more than 80%. Finally, after 21 days of biofilm formation, the removal rate reached 91.36% when the inlet concentration was 609 mg / m 3 g / L. At this time, the biofilm formation was basically completed, and the biofilm formation time was 21 days. After the biofilm formation was completed, the bio-trickling tower was continuously and stably operated for 21 days. The toluene inlet concentration was about 600 mg / m 3 g / L, the removal rate remained more than 90%, and the outlet concentration was as high as 55.46 mg / m3 During stable operation, the concentration of toluene in the exhaust gas was consistently below the maximum permissible emission concentration of 60 mg / m³ as specified in the "Integrated Emission Standard of Air Pollutants" (GB16297-1996). 3 .

[0060] Example 3

[0061] To address the high moisture content of the multiphase extraction tail gas, after the biotrickling filter was running stably, the relative humidity (RH) of the inlet air was varied to 34% and 87%, respectively. The toluene removal rates of the biotrickling filter and activated carbon adsorption were compared. The inlet gas flow rate was 4 L / min, the spray rate was 60 mL / min, and the inlet gas concentration was 600 mg / m³. 3 The removal rates of bio-trickling filters and activated carbon adsorption towers are as follows: Figure 4 As shown, the removal rate of toluene by the bio-trickling filter remained almost stable at a high level of around 91% within 9 hours under different relative humidity conditions, indicating that changes in the moisture content of the inlet air had no effect on the removal capacity of the bio-trickling filter. Activated carbon adsorption reached 0% in approximately 8.25 hours at RH 34%, indicating adsorption equilibrium. At RH 87%, the activated carbon adsorption reached adsorption equilibrium in approximately 4.25 hours, about 4.0 hours earlier than at RH 34%. This suggests that increased moisture content in the inlet air leads to a decrease in the adsorption capacity of activated carbon, resulting in earlier adsorption equilibrium, increased activated carbon consumption, and higher treatment costs.

[0062] Example 4

[0063] After the bio-trickling filter was running stably, the circulating liquid spray rate was changed to 30 mL / min, 45 mL / min, 60 mL / min, 75 mL / min, and 90 mL / min, with an inlet gas flow rate of 3–8 L / min and an inlet gas concentration of 600 mg / m³. 3 During the process, all conditions except for the spray volume remained unchanged. The change in toluene removal rate with spray volume is shown below. Figure 5 As shown, both excessive and insufficient spray volume lead to a decrease in removal rate. When the spray volume is 30 mL / min, the removal rate is only 82.18%. The optimal spray volume was found to be around 60 mL / min, with the optimal spray volume being 55 mL / min, at which point a removal rate of 91.72% was achieved.

[0064] Example 5

[0065] To address the significant concentration fluctuations in the tail gas from multiphase extraction, the removal rate of a bio-trickling filter under unsteady-state conditions with concentration fluctuations was investigated. The spray rate was 55 mL / min, the inlet gas flow rate was 4 L / min, and the inlet gas concentration was adjusted every 1 hour. The experimental results are as follows:Figure 6 The inlet concentration was controlled at 600 mg / m 3 The removal rate remained above 92% and the inlet concentration was increased to 745 mg / m 3 3 The removal rate of the biotrickling tower decreased from 97.61% to 68.53% when it was subjected to a high concentration of toluene. After that, the biotrickling tower was operated for 1 h at an inlet concentration of 546 mg / m 3 and 674 mg / m 3 The inlet concentration was adjusted to the level before the biotrickling tower was subjected to the high concentration of toluene. The removal rate of the biotrickling tower decreased by only 5.6% at the same inlet concentration, which did not cause a significant impact. This indicates that the biotrickling tower can still operate at a high removal rate after being subjected to a high concentration of toluene and can adapt to non-steady-state inlet conditions with fluctuating concentrations.

[0066] The above description of the embodiments is provided to enable those with ordinary skill in the art to understand and use the invention. Those with ordinary skill in the art can easily make various modifications to the embodiments and apply the general principles described herein to other embodiments without having to go through inventive labor. Therefore, the present invention is not limited to the above-described embodiments, and improvements and modifications made by those with ordinary skill in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of the present invention.​

Claims

1. A method for rapid biofilm formation in a low-carbon biotrickling column for the purification of multi-phase extraction off-gases, characterized by, The method comprises the following steps: (1) taking the high-efficiency degrading bacteria to be placed in a culture medium added with benzene series to carry out expansion culture, and obtaining a high-efficiency degrading bacteria suspension; (2) mixing the high-efficiency degrading bacteria suspension with activated sludge to obtain a composite bacteria group suspension; (3) adding the composite bacteria group suspension and a nutrient solution into a biological trickling filter tower to inoculate, and inputting benzene series gas, so that the composite bacteria group is subjected to gas-liquid phase synchronous domestication and membrane formation in the biological trickling filter tower, and the process is completed; The high-efficiency degrading bacteria are selected from at least one of the following categories: Corynebacterium praecipitate (a benzene-degrading bacterium) Corynebacterium The strain code is AL-5, and it is deposited at the China Center for Type Culture Collection (CCTCC) with accession number CCTCC NO. M2020503, or it may be an Achromobacterium (sp.). Achromobacter The strain, ED-2, is deposited at the China Center for Type Culture Collection (CCTCC) with accession number CCTCC NO. M2021058, or is a beneficial bacterium (sp.). Diaphorobacter The strain (sp.), with strain code ED-3, is deposited at the China Center for Type Culture Collection (CCTCC) with accession number CCTCC NO. M 2021059.

2. The method according to claim 1, wherein the method is characterized in that, OD value of the bacterial suspension of the high-efficiency degrading bacteria 600 0.8-1.

5.

3. The method according to claim 1, wherein the method is characterized by, In step (1), the benzene series in the culture medium added with benzene series is toluene, and the concentration is 20 mg / L.

4. The method according to claim 1, wherein the method is characterized in that, In step (2), the volume ratio of the high-efficiency degrading bacteria suspension to the activated sludge is 0.5-1:

1.

5. The method according to claim 1, wherein the method is characterized in that, In step (2), the activated sludge used is from a water treatment plant, and the SV is 30%-50%, and the SVI is 60-100 mL / g.

6. The method according to claim 1, wherein the method is characterized in that, In step (3), the nutrient solution is configured by 0.2 g / L NH4Cl, 7.95 g / L NaCl, 0.77 g / L MgCl2·6H2O, 1.05 g / L MgSO4·7H2O, 0.076 g / L CaCl2, 0.22 g / L KCl, 0.01 g / L NaHCO3, 0.026 g / L NaBr, 0.25 g / L K2HPO4, 0.2-1.0 g / L yeast powder, and trace elements.

7. The method according to claim 1 or 6, wherein the method is characterized in that, In step (3), the nutrient solution also contains benzene series components, the benzene series is toluene, the mass concentration is increased by 10 mg / L every day from 0 mg / L on the first day of membrane formation, and is gradually increased to 30-60 mg / L and then terminated.

8. The method according to claim 1, wherein the method is characterized by, In step (3), the benzene series gas introduced is toluene dilution gas, and the mass concentration is increased by 50-100 mg / m 3 from the first day of the membrane hanging, 50-100 mg / m 3 every 1-2 days, and gradually increased to 400-1000 mg / m 3 .

9. The method according to claim 1, wherein the method is characterized by, In step (3), the carrier filled in the biological trickling filter tower is polyurethane sponge filler.

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